OK,

This is sick! My clutch started slipping and I lost about 1L of Mobil 1 every 3 weeks so I decided to do the clutch, seals and gaskets and the list is phenomenal...front 3 seals, valve cover, distributor seals, rear crank, reak crank flange and oil pan...along with the clutch and timing belt.

SO after all this was done (plus cleaning my PCV condenser and replacing the flamre trap nipple) my car decided to make a new oil leak...OUT THE OIL CAP...and all over the turbo. Now I leak AND burn oil like my engine is on fire!!!

So, what the heck is wrong with my car...I am thinking (shudder) blowby but I have no clue really how to check that. What else could it POSSIBLY be and is it worth fixing it...grrrr...I have put about $6000 into my brick in since I bought it 7 mos ago and I am tired of new problems.

Also, anyone knwo a good, chap volvo mechanic in the Toronto area?

Thanks...Russ

1987 745T 370,00km

So...here's a little update for anyone still listening. As far as I know the PCV breather box, condenser and hoses are all working. THe seal on the oil cap may not be the best, but its the pressure that is making it leak, not the seal. Fixing the seals will not fix the pressure problems even if they slow the leak. I had an idea to test if the intake manifold pressure line was not working but the air intake line was so I held my hand over the oil cap and ran up the throttle...I could still feel pressure but it didn't really seem to increase.

Anyways...aside from PCV hose problems and blowby, WHAT ELSE IS COULD BE DOING THIS? Also, what is the best home remedy to test for the blowby?

Thanks

All these replys are on the right track I think...If I were you...I would replace ALL the vacuum hoses. I know it sounds like throwing parts at a problem but it really sounds to me like that is the problem. Blowing through a hose may make you think it is clear but if its walls are weak, vacuum can quickly close them or expose a leak. A modest investment in new hoses may save you $$ in the long run. And it never hurts to have new hoses! Good luck.

Just FYI your car doesnt have the firetrap in it, yours goes directly into the turbo to recir the air, check that hose flying over the top of the engine from that oil breather box which goes directly into the turbo intake system., from what your sounding like you must have something clogged somewhere, if you had bad rings youd be blowing oil out the tail pipe as well as what your describing i have yet to hear of a 700 with bad rings. Check your timeing make sure it hasnt slipped a tooth if it has that could be the cause of your pressure under the valve cover. its possible

Dumb question but do you have the rubber gasket installed in the cap, does the cap fit ecurely?. If yes to above you must be building pressure up in the crankcase, the flame trap/breathing system is designed to actually create negative crankcase pressure and feed fumes into the air intake system.
Under these conditions oil will not go out at the cap.

You said that you replaced the flame trap nipple. Do you mean the brass nipple which theads into the manifold to provide a vacume source. Did you also check the inside of the flame trap to make sure the screen is not clogged? If clogged this will allow blowby however slight to create positive pressure and blow oil out.

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David Hunter

I replaced the 'breather nipple' which is the flame trap for the turbo model...I have checked most of the hoses going in and out (at least blown thru them) and I will double-check to make sure but I don't think its the problem.

My old oil cap had the fins bent a little but the new one has a seal and good fins...so say it IS crankcase pressure, what are my options?

Did not realize you had a turbo. I am not familiar with the turbo plumbing. The bottom line is that you cannot have positive pressure in the crankcase. I think you can check for this same as I have done on my non turbo. Engine running, remove cap and place palm over the filler hole to form a seal, hold for a short time and you should be able to feel if there is a slight pressure or vacume. Double check that new cap and where it seals.

It is doubtfull that you have blowby to the extent that it is building pressure beyond the capacity of the crankcase venting sytem to handle it. If indeed this is the case the next step would be a compression test to see the condition of the rings.

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David Hunter

I assume you also checked to make sure the hose going from the flame trap to the nipple is not plugged?

Jeff Pierce
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'93 945 Turbo ( one kickass family car ! ), '92 Mercedes 190E (my daily driver), '53 Willys-Overland Pickup (my snow-plow truck/conversation piece)

check the breather box, breather hose, and the flame trap assembly. there is no actual flame trap inside the assembly, but it's the same basic layout. procedure's in the FAQ.
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'

Hmm...I called it the condenser but I meant the breather box...cleaned that and all the vacuum hoses too, that was an easy one!